def pair_with_targetsum(arr, target_sum):
  start = 0
  end = len(arr) - 1
  
  for x in range(len(arr)):
    if arr[start]+arr[end] == target_sum:
      return [start,end]
    elif((arr[start]+arr[end])>target_sum):
      end -= 1
    else:
      start += 1
  # TODO: Write your code here
  return [-1, -1]


def main():
  print(pair_with_targetsum([1, 2, 3, 4, 6], 6))
  print(pair_with_targetsum([2, 5, 9, 11], 11))


main()
